The Messenger of Allah, the Prophet Muhammed (PBUH), said:
The day of Ghadeer Khumm is the best holiday of my nation, and it is the day on which Allah Almighty commanded me to appoint my brother Ali bin Abi Talib as a leader for my nation, by whom they will be guided after me. It is the day on which Allah perfected the religion, completed His blessing upon my nation, and approved Islam as their religion.
*Al-Amali (by Al-Saduq), p.126
Congratulations on the Greatest Eid of Allah, Eid Al-Ghadeer Al-Ghar [The Glorious]. May Allah strengthen our allegiance to the Commander of the Faithful Imam Ali (PBUH).